Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Description discloses important traits beyond annotations: 'scoped by your identifier,' 'authenticated users get persistent memory; anonymous sessions retain memory for 24 hours,' and the key-value storage model. This adds context about data retention and scoping that annotations do not provide. No contradictions with the given annotations (idempotentHint=true, destructiveHint=false, readOnly=false).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences, front-loaded with purpose, then usage, then storage details and sibling references. Every sentence earns its place with no fluff or redundancy. It is concise yet information-dense.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple two-parameter tool, the description covers purpose, when to use, persistence behavior, scoping, and how it relates to sibling tools (recall, forget). No output schema exists, and the description does not need to explain return values for a save operation. It is sufficiently complete for an agent to invoke correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with descriptions for both key and value parameters. The description reinforces parameter semantics by giving domain-specific examples of keys ('resolved ticker, target address, user preference') and values ('findings, addresses, preferences, notes'), adding value beyond the schema's generic examples.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Save data the agent will need to reuse later.' It specifies the action (save), resource (data/key-value pair), and scope (across conversation or sessions). It also distinguishes itself from siblings by mentioning recall and forget as complementary tools for retrieval and deletion.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicit guidance is provided: 'Use when you discover something worth carrying forward' with concrete examples like 'a resolved ticker, a target address, a user preference, a research subject.' It also gives a clear exclusion by telling the agent to pair with recall for retrieval and forget for deletion, preventing misuse.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.